1. Field of the Invention
The present invention is related to a method for producing a ratchet bushing used in a bicycle, more particularly to a producing process for forming the ratchet bushing of bicycle.
2. Description of the Prior Art
A conventional method for producing a bicycle ratchet bushing is shown in FIG. 5, wherein, the ratchet bushing 70 is formed by processing a fundamental material 50 to be treated by means of extrusion process 61, cutting process 62, annealing process 63, coating treatment 64, cold forging process 65, turning or drilling process 66, solid solution treatment 67, artificial aging treatment 68 and surface treatment 69.
In addition, one conventional method for producing a rod by drawing method, an extruded material 50 is applied to a head-hitting process 81 (not shown) to narrow down the shape of the head of the extruded material 50, so that it can be penetrated through the mold of the drawing machine to proceed with the manufacturing of drawing process 80. However, the conventional method has contained some improvable defects, such as:
1. Higher damage rate of the work: due to the process of head-hitting is applied to the extruded material, the shape of the extruded material could possibly be destroyed or deformed during the hitting process, resulting in the difficulty of the extruded material to penetrate into the mold of the drawing machine; or the outline of the extruded material could possibly be changed during the hitting process, resulting in an uneven reduction of the thickness to the extruded material when processing of the drawing, and that will influence the consistence of smoothness of the extruded material on its surface or size, to finally result in the scrap of the product. Therefore, the damage rate of the products is extremely high; and
2. Inefficiency of manufacturing control: since the conventional method of producing the bicycle ratchet bushing, the fundamental material has to be treated by extrusion process, cutting process, annealing process, coating treatment, cold forging process, turning or drilling process, solid solution treatment, artificial aging treatment and surface treatment, so as the ratchet bushing is to be formed. However, the aforesaid manufacturing processes are very trivial and complicated, besides, a forging mold for the cold forging process is needed to be redesigned, and that would lead the manufacturing costs to increase significantly, as well as the inefficiency of manufacture. Therefore, the manufacturing control of the working process is poor.
The present invention is intended to improve the above mentioned drawbacks of the conventional method of producing the bicycle ratchet bushing. The present invention provides improved solutions to the problems of high damage rate of the work and Inefficiency of manufacturing control.